Further header cleanup and a few updates

Updated llstring to current linden
Further linden_common cleanup
Header cleanup
Raised banlines to 5000 as per linden server change
Included missing llmediaentry.cpp file
Minor whitespace changes here and there

indra/llmessage/lliohttpserver.cpp

@@ -33,7 +33,6 @@
 #include "llapr.h"
 #include "llbuffer.h"
 #include "llbufferstream.h"
-#include "llfasttimer.h"
 #include "llhttpnode.h"
 #include "lliopipe.h"
 #include "lliosocket.h"